The present invention relates to a measuring apparatus for the noninvasive determination of peripheral blood outflow and flow disturbances in the extremities of human beings. Measuring devices of this type are disclosed in, by way of illustration, German Patent No. 31 00 610.8 or German Patent No. 33 18 746.0. In the measuring device disclosed in DE-PS No. 31 00 610.8, the temporal course of the reflected or dispersed back part of the radiation is evaluated in an analog manner and recorded by means of a recording device. In the measuring device disclosed in DE-PS No. 33 18 746.0, the analog signal is translated or converted into a digital signal by means of a transmission-reception data connection point circuit and transferred to a calculator device. The calculator device calculates the physical rating parameters for the analog light reflection curves. This measuring device is, accordingly, particularly suitable for conducting and evaluating a test series.
Both prior art measuring devices share the drawback that they cannot easily be constructed as handy, portable apparatuses: neither the recording device described in DE-PS No. 31 00 610.8 nor the common micro-computer with floppy disk drives, etc. described in DE-PS No. 33 18 746.0 can be miniaturized to the extent that they can be readily fabricated into a portable apparatus. Moreover, the power consumption of the prior art measuring devices is too great for portable apparatuses.
It is especially disadvantageous with regard to the prior art measuring devices that the operating staff determines the commencement and the termination of each measurement, thereby making subjective measurement errors possible.